Sexual Reproduction

Science, Grade 6


Table Of Contents: Sexual Reproduction

1. Sex Cells - Sperm and Eggs
Meiosis is a process that occurs in male and female reproductive organs. Meiosis forms sex cells--sperm and eggs. These cells have half the number of chromosomes as the parent cell.
2. Egg Fertilization
During sexual reproduction, a sperm fertilizes an egg, and the genetic information from the parents is combined. The fertilized egg is called a zygote.
3. Sex Cell Chromosomes
A human sex cell has 23 chromosomes. At fertilization, the chromosomes from the egg and sperm combine to form a zygote with 46 chromosomes.
4. The Zygote
The zygote contains all the information needed to form a new organism. Every cell of the organism descends from this original cell.